Various types of cooling mechanisms can be used to remove waste heat from high power semiconductor devices such as power FETs and IGBTs. In cases where the waste heat and/or the ambient temperature are very high, the power device packages can be thermally coupled to a liquid cooled heat exchanger. For example, the U.S. Pat. No. 6,639,798 to Jeter et al. illustrates an electronics assembly including a liquid cooled heat exchanger having an internal fin structure for increasing the effective surface area for heat exchange. Nevertheless, the thermal resistance between the power device package and the heat exchanger can significantly limit the heat transfer capability of the assembly. Furthermore, only one side of the power device package can be thermally coupled to the heat exchanger in most cases. Accordingly, what is desired is a liquid cooled packaging arrangement for power semiconductor devices that maximizes thermal coupling between the power devices and the liquid coolant and provides double-sided cooling of the power device packages.